1. Field of the Invention
The present invention relates to an image-taking apparatus to which an accessory such as a tripod can be attached, and more particularly, to a structure which attaches an accessory.
2. Description of the Related Art
Through the realization of low running cost by a recording/reproducing function using a recording medium and size and weight reductions, the demand for a digital still camera is growing in recent years. On the other hand, the bottom face of a camera is provided with a mounting member to mount a tripod and a screw hole portion is formed in this mounting member to screw in a screw portion provided on the tripod.
This mounting member is disclosed in Japanese Patent Application Laid-Open No. H14(2002)-006381 and the structure is shown in FIG. 9 and FIG. 10. Here, FIG. 9 shows the mounting member attached to a main chassis which is an internal structure of a camera and FIG. 10 is a cross-sectional view in the thickness direction of the mounting member.
A mounting member 118 is fixed to a main chassis 109, a bottom plate 119 and, a front cover and a rear cover (not shown) which constitute the exterior of the camera by using screws. The main chassis 109 is constructed of a thin steel sheet in consideration of size and weight reductions.
As shown in FIG. 10, a screw hole portion 121 is formed in the mounting member 118 and the camera is fixed to the tripod by screwing a screw portion (not shown) provided for the tripod into this screw hole portion 121.
Here, since the screw hole portion 121 is formed by screwing a tap into a concave section provided in the mounting member 118, the area of a screw groove formed near the bottom of this concave section becomes an incomplete screw portion 121a. Therefore, when the screw portion of the tripod is screwed into the screw hole portion 121, this screw portion may be caught in the incomplete screw portion 121a, making it difficult to remove the screw portion from the mounting member 118.
Thus, a semi-spherical protrusion 121b having substantially the same height as that of the area in which the incomplete screw portion 121a is formed is provided on the bottom face of the concave section beforehand to prevent the screw portion of the tripod from going into the incomplete screw portion 121a. That is, when the screw portion of the tripod is screwed into the screw hole portion 121, the tip of this screw portion touches the protrusion 121b preventing the screw portion from further going into the incomplete screw portion 121a. 
Furthermore, there is conventionally a proposal on a camera provided with a contact section called a “hot shoe” at the top of the camera body so as to mount an external electronic flash on this contact section.
Furthermore, there is a proposal on a camera provided with a remote control reception section inside the camera body to allow various remote control operations by remote control.
However, when a normal tap is used, a tip of the tap touches the protrusion 121b which makes it difficult to machine the necessary screw portion. For this reason, it is necessary to form the screw hole portion 121 using a special tap to avoid interference with the protrusion 121b, but using the special tap may increase the machining cost.
Furthermore, the thickness of the mounting member 118 is the sum of the screw hole portion 121, protrusion 121b and ceiling section 122, which may not only narrow the internal volume of the camera but also increase the size of the camera.
Moreover, when an external electronic flash is mounted on the camera as described above, it is necessary to increase the thickness of the area peripheral to the contact section to support the electronic flash, which may increase the size of the camera.
Furthermore, when a remote control reception section is provided inside the camera body, it is necessary to secure a space to place this remote control reception section, which may increase the size of the camera.